1. Field
Embodiments of the present invention relate to tire air-pressure detection devices, and more particularly to tire air-pressure detection devices which have a holding structure capable of withstanding even a large centrifugal force generated due to high-speed rotation of a wheel.
2. Description of Related Art
There has been known a tire air pressure monitoring system which can check an air pressure of each tire from a driver seat by constantly measuring air pressures of tires. Japanese Patent Publication JP-A-2004-317198 (‘JP '198) proposes an air pressure sensor which is mounted on a portion of a rim of a tire wheel, wherein a mounting portion on an outer casing of the air pressure sensor is formed in a shape which conforms to a curvature shape of the rim, and the mounting portion is mounted on a portion of the rim by way of an adhesive means.
In such an air pressure sensor, a battery and a detector (sensor portion) are housed in a resin casing, and an outer casing of the resin casing which is split in two is formed by assembling two split casings using a large number of small bolts or is formed by integral molding.